Generalized Anxiety Disorder
Generalized Anxiety Disorder (GAD) is much more than the normal anxiety people experience day to day. It's chronic and exaggerated worry and tension, even though nothing seems to provoke it. Having this disorder means always anticipating disaster, often worrying excessively about health, money, family or work. Sometimes, though, the source of the worry is hard to pinpoint. Simply the thought of getting through the day provokes anxiety.

People with GAD can't seem to shake their concerns, even though they usually realize that their anxiety is more intense than the situation warrants. People with GAD also seem unable to relax. They often have trouble falling or staying asleep. Their worries are accompanied by physical symptoms, especially trembling, twitching, muscle tension, headaches, irritability, sweating or hot flashes. They may feel lightheaded or out of breath.

Many individuals with GAD startle more easily than other people. They tend to feel tired, have trouble concentrating, and sometimes suffer from depression. Impairments associated with GAD may take the form of nausea, frequent trips to the bathroom or feeling like there is a lump in the throat.

GAD comes on gradually and most often hits people in childhood or adolescence, but can begin in adulthood, too. It's more common in women than in men and often occurs in relatives of affected persons. About 3 to 4 percent of the U.S. population has GAD during the course of a year.

Symptoms
Generalized Anxiety Disorder (GAD) is characterized by six months or more of chronic, exaggerated worry and tension that is unfounded or much more severe than the normal anxiety most people experience. People with this disorder usually:

Expect the worst

Worry excessively about money, health, family or work, even when there are no signs of trouble

Causes
Like heart disease and diabetes, anxiety disorders are complex and probably result from a combination of genetic, behavioral, developmental and other factors.

Several parts of the brain are key actors in a highly dynamic interplay that gives rise to fear and anxiety. Using brain imaging technologies and neurochemical techniques, scientists are finding that a network of interacting structures is responsible for these emotions. Much research centers on the amygdala, an almond-shaped structure deep within the brain. The amygdala is believed to serve as a communications hub between the parts of the brain that process incoming sensory signals and the parts that interpret them. It can signal that a threat is present, and trigger a fear response or anxiety. It appears that emotional memories stored in the central part of the amygdala may play a role in disorders involving very distinct fears, like phobias, while different parts may be involved in other forms of anxiety.

By learning more about brain circuitry involved in fear and anxiety, scientists may be able to devise new and more specific treatments for anxiety disorders. For example, it someday may be possible to increase the influence of the thinking parts of the brain on the amygdala, thus placing the fear and anxiety response under conscious control. In addition, with new findings about neurogenesis (birth of new brain cells) throughout life, perhaps a method will be found to stimulate growth of new neurons in the hippocampus in people with severe anxiety.

NIMH-supported studies of twins and families suggest that genes play a role in the origin of anxiety disorders. But heredity alone can't explain what goes awry. Experience also plays a part. In PTSD, for example, trauma triggers the anxiety disorder; but genetic factors may explain why only certain individuals exposed to similar traumatic events develop full-blown PTSD. Researchers are attempting to learn how genetics and experience interact in each of the anxiety disorders - information they hope will yield clues to prevention and treatment.

Panic Disorder
Panic disorder is characterized by unexpected and repeated episodes of intense fear accompanied by physical symptoms that may include chest pain, heart palpitations, shortness of breath, dizziness or abdominal distress. These sensations often mimic symptoms of a heart attack or other life-threatening medical conditions. As a result, the diagnosis of panic disorder is frequently not made until extensive and costly medical procedures fail to provide a correct diagnosis or relief.

Many people with panic disorder develop intense anxiety between episodes. It is not unusual for a person with panic disorder to develop phobias about places or situations where panic attacks have occurred, such as in supermarkets or other everyday situations. As the frequency of panic attacks increases, the person often begins to avoid situations where they fear another attack may occur or where help would not be immediately available. This avoidance may eventually develop into agoraphobia, an inability to go beyond known and safe surroundings because of intense fear and anxiety.

Fortunately, through research supported by the National Institute of Mental Health (NIMH) and the industry, effective treatments have been developed to help people with panic disorder.

About 1.7 percent of the adult U.S. population ages 18 to 54 - approximately 2.4 million people - has panic disorder in a given year. Women are twice as likely as men to develop panic disorder. Panic disorder typically strikes in young adulthood. Roughly half of all people who have panic disorder develop the condition before age 25.

Symptoms
To make a formal diagnosis of panic disorder, a person must experience either four panic attacks within a four-week period, or one or more attacks followed by at least a month of persistent fear of having another attack. During one of those attacks a minimum of four of these symptoms reach a peak within 10 minutes.

Palpations, pounding heart or accelerated heart rate

Trembling or shaking

Sensations of shortness of breath or smothering

Feeling of choking

Chest pain or discomfort

Nausea or abdominal distress

Feeling dizzy, unsteady, lightheaded or faint

Feeling detached from oneself or feelings of unreality

Fear of losing control or of going crazy

Fear of dying

Numbness or tingling sensation

Chills or hot flashes

Causes
Heredity, thinking in a way that exaggerates relatively normal bodily reactions, stressful life events and other biological factors are all believed to play a role in the onset of panic disorder. The exact cause or causes of panic disorder are unknown and are the subject of intense scientific investigation.

Studies in animals and humans have focused on pinpointing the specific brain areas and circuits involved in anxiety and fear, which underlie anxiety disorders such as panic disorder. Fear, an emotion that evolved to deal with danger, causes an automatic, rapid protective response that occurs without the need for conscious thought. It has been found that the body's fear response is coordinated by a small structure deep inside the brain, called the amygdala. Although relatively small, the amygdala is a very complicated structure, and recent research suggests that anxiety disorders may be associated with abnormal activity in the amygdala.

Social Phobia
Social phobia, also called social anxiety, is a disorder characterized by overwhelming anxiety and excessive self-consciousness in everyday social situations. People with social phobia have a persistent, intense and chronic fear of being watched and judged by others and of being embarrassed or humiliated by their own actions. Their fear may be so severe that it interferes with work or school and other ordinary activities. While many people with social phobia recognize that their fear of being around people may be excessive or unreasonable, they are unable to overcome it. They often worry for days or weeks in advance of a dreaded situation.

Social phobia can be limited to only one type of situation - such as a fear of speaking in formal or informal situations, or eating or drinking in front of others - or, in its most severe form, may be so broad that a person experiences symptoms almost any time they are around other people. Social phobia can be very debilitating - it may even keep people from going to work or school on some days. Many people with this illness have a hard time making and keeping friends.

Physical symptoms often accompany the intense anxiety of social phobia and include blushing, profuse sweating, trembling and other symptoms of anxiety such as difficulty talking, and nausea or other stomach discomfort. These visible symptoms heighten the fear of disapproval and the symptoms themselves can become an additional focus of fear. Fear of symptoms can create a vicious cycle: as people with social phobia worry about experiencing the symptoms, the greater their chances of developing the symptoms. Social phobia often runs in families and may be accompanied by depression or alcohol dependence.

Prevalence of Social Phobia
About 3.7 percent of the U.S. population ages 18 to 54 - approximately 5.3 million Americans - has social phobia in any given year. Social phobia occurs twice as often in women as in men, although a higher proportion of men seek help for this disorder. The disorder typically begins in childhood or early adolescence and rarely develops after age 25.

Symptoms
A diagnosis of social phobia is made only if the avoidance, fear or anxious anticipation of encountering the social or performance situation interferes with the person's daily routine, occupational functioning or social life, or if the person is markedly distressed by having the phobia.

Symptoms include:

Fear of one or more social or performance situations if the person is exposed to unfamiliar people and the individual fears that he or she will behave in a manner that causes embarrassment

Exposure to social situation causes intense anxiety

The level of anxiety is recognized by the individual as excessive

The feared situation must be avoided or endured with anxiety and distress

The avoidance, anxious anticipation or distress interferes significantly with the person's social, academic or occupational functioning

Causes
Research to define causes of social phobia is ongoing. Some investigations implicate a small structure in the brain called the amygdala in the symptoms of social phobia. The amygdala is believed to be a central site in the brain that controls fear responses.

Animal studies are adding to the evidence that suggests social phobia can be inherited. In fact, researchers supported by the National Institute of Mental Health (NIMH) recently identified the site of a gene in mice that affects learned fearfulness.

One line of research is investigating a biochemical basis for the disorder. Scientists are exploring the idea that heightened sensitivity to disapproval may be physiologically or hormonally based.

Other researchers are investigating the environment's influence on the development of social phobia. People with social phobia may acquire their fear from observing the behavior and consequences of others, a process called observational learning or social modeling.

Obsessive-Compulsive Disorder
Obsessive-ompulsive disorder (OCD), one of the anxiety disorders, is a potentially disabling condition that can persist throughout a person's life. The individual who suffers from OCD becomes trapped in a pattern of repetitive thoughts and behaviors that are senseless and distressing but extremely difficult to overcome. OCD occurs in a spectrum from mild to severe, but if severe and left untreated, it can destroy a person's capacity to function at work, at school or even in the home.

For many years, mental health professionals thought of OCD as a rare disease because only a small minority of their patients had the condition. The disorder often went unrecognized because many of those afflicted with OCD, in efforts to keep their repetitive thoughts and behaviors secret, failed to seek treatment. This led to underestimates of the number of people with the illness. However, a survey conducted in the early 1980s by the National Institute of Mental Health (NIMH) - the Federal agency that supports research nationwide on the brain, mental illnesses and mental health - provided new knowledge about the prevalence of OCD. The NIMH survey showed that OCD affects more than 2 percent of the population, meaning that OCD is more common than such severe mental illnesses as schizophrenia, bipolar disorder or panic disorder. OCD strikes people of all ethnic groups. Males and females are equally affected. The social and economic costs of OCD were estimated to be $8.4 billion in 1990.

Although OCD symptoms typically begin during the teenage years or early adulthood, recent research shows that some children develop the illness at earlier ages, even during the preschool years. Studies indicate that at least one-third of cases of OCD in adults began in childhood. Suffering from OCD during early stages of a child's development can cause severe problems for the child. It is important that the child receive evaluation and treatment by a knowledgeable clinician to prevent the child from missing important opportunities because of this disorder.

Symptoms

Obsessions
These are unwanted ideas or impulses that repeatedly well up in the mind of the person with OCD. Persistent fears that harm may come to self or a loved one, an unreasonable concern with becoming contaminated, or an excessive need to do things correctly or perfectly are common. Again and again, the individual experiences a disturbing thought, such as, "My hands may be contaminated, I must wash them," "I may have left the gas on" or "I am going to injure my child." These thoughts are intrusive, unpleasant and produce a high degree of anxiety. Sometimes the obsessions are of a violent or a sexual nature, or concern illness.

Compulsions
In response to their obsessions, most people with OCD resort to repetitive behaviors called compulsions. The most common of these are washing and checking. Other compulsive behaviors include counting (often while performing another compulsive action such as hand-washing), repeating, hoarding, and endlessly rearranging objects in an effort to keep them in precise alignment with each other. Mental problems, such as mentally repeating phrases, list-making or checking are also common. These behaviors generally are intended to ward off harm to the person with OCD or others. Some people with OCD have regimented rituals while others have rituals that change. Performing rituals may give the person with OCD some relief from anxiety, but it is only temporary.

People with OCD show a range of insight into the senselessness of their obsessions. Often, especially when they are not actually having an obsession, they can recognize that their obsessions and compulsions are unrealistic. At other times they may be unsure about their fears or even believe strongly in their validity.

Most people with OCD struggle to banish their unwanted, obsessive thoughts and to prevent themselves from engaging in compulsive behaviors. Many are able to keep their obsessive-compulsive symptoms under control during the hours when they are at work or attending school. But over the months or years, resistance may weaken, and when this happens, OCD may become so severe that time-consuming rituals take over the sufferers' lives, making it impossible for them to continue activities outside the home.

OCD sufferers often attempt to hide their disorder rather than seek help. Often they are successful in concealing their obsessive-compulsive symptoms from friends and coworkers. An unfortunate consequence of this secrecy is that people with OCD usually do not receive professional help until years after the onset of their disease. By that time, they may have learned to work their lives - and family members' lives - around the rituals.

OCD tends to last for years, even decades. The symptoms may become less severe from time to time, and there may be long intervals when the symptoms are mild, but for most individuals with OCD, the symptoms are chronic.

Causes
The old belief that OCD was the result of life experiences has been weakened before the growing evidence that biological factors are a primary contributor to the disorder. The fact that OCD patients respond well to specific medications that affect the neurotransmitter serotonin suggests the disorder has a neurobiological basis. For that reason, OCD is no longer attributed only to attitudes a patient learned in childhood - for example, an inordinate emphasis on cleanliness, or a belief that certain thoughts are dangerous or unacceptable. Instead, the search for causes now focuses on the interaction of neurobiological factors and environmental influences, as well as cognitive processes.

OCD is sometimes accompanied by depression, eating disorders, substance abuse disorder, personality disorders, attention deficit disorder, or another of the anxiety disorders. Coexisting disorders can make OCD more difficult both to diagnose and to treat.

In an effort to identify specific biological factors that may be important in the onset or persistence of OCD, NIMH-supported investigators have used a device called the positron emission tomography (PET) scanner to study the brains of patients with OCD. Several groups of investigators have obtained findings from PET scans suggesting that OCD patients have patterns of brain activity that differ from those of people without mental illness or with some other mental illness. Brain-imaging studies of OCD showing abnormal neurochemical activity in regions known to play a role in certain neurological disorders suggest that these areas may be crucial in the origins of OCD. There is also evidence that treatment with medications or behavior therapy may induce changes in the brain that coincide with clinical improvement.

Preliminary studies of the brain using magnetic resonance imaging showed that the subjects with obsessive-compulsive disorder had significantly less white matter than did normal control subjects, suggesting a widely distributed brain abnormality in OCD. Understanding the significance of this finding will be further explored by functional neuroimaging and neuropsychological studies.

Symptoms of OCD are seen in association with some other neurological disorders. There is an increased rate of OCD in people with Tourette's syndrome, an illness characterized by involuntary movements and vocalizations. Investigators are currently studying the hypothesis that a genetic relationship exists between OCD and the tic disorders.

Other illnesses that may be linked to OCD are trichotillomania (the repeated urge to pull out scalp hair, eyelashes, eyebrows or other body hair), body dysmorphic disorder (excessive preoccupation with imaginary or exaggerated defects in appearance), and hypochondriasis (the fear of having - despite medical evaluation and reassurance - a serious disease). Genetic studies of OCD and other related conditions may enable scientists to pinpoint the molecular basis of these disorders.

Other theories about the causes of OCD focus on the interaction between behavior and the environment and on beliefs and attitudes, as well as how information is processed. These behavioral and cognitive theories are not incompatible with biological explanations.

A person with OCD has obsessive and compulsive behaviors that are extreme enough to interfere with everyday life. People with OCD should not be confused with a much larger group of individuals who are sometimes called "compulsive" they hold themselves to a high standard of performance and are perfectionists and very organized in their work and even in recreational activities. This type of "compulsiveness" often serves a valuable purpose, contributing to a person's self-esteem and success on the job. In that respect, it differs from the life-wrecking obsessions and rituals of the person with OCD.

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Generalized Anxiety Disorder
Generalized Anxiety Disorder (GAD) is much more than the normal anxiety people experience day to day. It's chronic and exaggerated worry and tension, even though nothing seems to provoke it. Having this disorder means always anticipating disaster, often worrying excessively about health, money, family or work. Sometimes, though, the source of the worry is hard to pinpoint. Simply the thought of getting through the day provokes anxiety.

People with GAD can't seem to shake their concerns, even though they usually realize that their anxiety is more intense than the situation warrants. People with GAD also seem unable to relax. They often have trouble falling or staying asleep. Their worries are accompanied by physical symptoms, especially trembling, twitching, muscle tension, headaches, irritability, sweating or hot flashes. They may feel lightheaded or out of breath.

Many individuals with GAD startle more easily than other people. They tend to feel tired, have trouble concentrating, and sometimes suffer from depression. Impairments associated with GAD may take the form of nausea, frequent trips to the bathroom or feeling like there is a lump in the throat.

GAD comes on gradually and most often hits people in childhood or adolescence, but can begin in adulthood, too. It's more common in women than in men and often occurs in relatives of affected persons. About 3 to 4 percent of the U.S. population has GAD during the course of a year.

Symptoms
Generalized Anxiety Disorder (GAD) is characterized by six months or more of chronic, exaggerated worry and tension that is unfounded or much more severe than the normal anxiety most people experience. People with this disorder usually:

Expect the worst

Worry excessively about money, health, family or work, even when there are no signs of trouble

Causes
Like heart disease and diabetes, anxiety disorders are complex and probably result from a combination of genetic, behavioral, developmental and other factors.

Several parts of the brain are key actors in a highly dynamic interplay that gives rise to fear and anxiety. Using brain imaging technologies and neurochemical techniques, scientists are finding that a network of interacting structures is responsible for these emotions. Much research centers on the amygdala, an almond-shaped structure deep within the brain. The amygdala is believed to serve as a communications hub between the parts of the brain that process incoming sensory signals and the parts that interpret them. It can signal that a threat is present, and trigger a fear response or anxiety. It appears that emotional memories stored in the central part of the amygdala may play a role in disorders involving very distinct fears, like phobias, while different parts may be involved in other forms of anxiety.

By learning more about brain circuitry involved in fear and anxiety, scientists may be able to devise new and more specific treatments for anxiety disorders. For example, it someday may be possible to increase the influence of the thinking parts of the brain on the amygdala, thus placing the fear and anxiety response under conscious control. In addition, with new findings about neurogenesis (birth of new brain cells) throughout life, perhaps a method will be found to stimulate growth of new neurons in the hippocampus in people with severe anxiety.

NIMH-supported studies of twins and families suggest that genes play a role in the origin of anxiety disorders. But heredity alone can't explain what goes awry. Experience also plays a part. In PTSD, for example, trauma triggers the anxiety disorder; but genetic factors may explain why only certain individuals exposed to similar traumatic events develop full-blown PTSD. Researchers are attempting to learn how genetics and experience interact in each of the anxiety disorders - information they hope will yield clues to prevention and treatment.

Panic Disorder
Panic disorder is characterized by unexpected and repeated episodes of intense fear accompanied by physical symptoms that may include chest pain, heart palpitations, shortness of breath, dizziness or abdominal distress. These sensations often mimic symptoms of a heart attack or other life-threatening medical conditions. As a result, the diagnosis of panic disorder is frequently not made until extensive and costly medical procedures fail to provide a correct diagnosis or relief.

Many people with panic disorder develop intense anxiety between episodes. It is not unusual for a person with panic disorder to develop phobias about places or situations where panic attacks have occurred, such as in supermarkets or other everyday situations. As the frequency of panic attacks increases, the person often begins to avoid situations where they fear another attack may occur or where help would not be immediately available. This avoidance may eventually develop into agoraphobia, an inability to go beyond known and safe surroundings because of intense fear and anxiety.

Fortunately, through research supported by the National Institute of Mental Health (NIMH) and the industry, effective treatments have been developed to help people with panic disorder.

About 1.7 percent of the adult U.S. population ages 18 to 54 - approximately 2.4 million people - has panic disorder in a given year. Women are twice as likely as men to develop panic disorder. Panic disorder typically strikes in young adulthood. Roughly half of all people who have panic disorder develop the condition before age 25.

Symptoms
To make a formal diagnosis of panic disorder, a person must experience either four panic attacks within a four-week period, or one or more attacks followed by at least a month of persistent fear of having another attack. During one of those attacks a minimum of four of these symptoms reach a peak within 10 minutes.

Palpations, pounding heart or accelerated heart rate

Trembling or shaking

Sensations of shortness of breath or smothering

Feeling of choking

Chest pain or discomfort

Nausea or abdominal distress

Feeling dizzy, unsteady, lightheaded or faint

Feeling detached from oneself or feelings of unreality

Fear of losing control or of going crazy

Fear of dying

Numbness or tingling sensation

Chills or hot flashes

Causes
Heredity, thinking in a way that exaggerates relatively normal bodily reactions, stressful life events and other biological factors are all believed to play a role in the onset of panic disorder. The exact cause or causes of panic disorder are unknown and are the subject of intense scientific investigation.

Studies in animals and humans have focused on pinpointing the specific brain areas and circuits involved in anxiety and fear, which underlie anxiety disorders such as panic disorder. Fear, an emotion that evolved to deal with danger, causes an automatic, rapid protective response that occurs without the need for conscious thought. It has been found that the body's fear response is coordinated by a small structure deep inside the brain, called the amygdala. Although relatively small, the amygdala is a very complicated structure, and recent research suggests that anxiety disorders may be associated with abnormal activity in the amygdala.

Social Phobia
Social phobia, also called social anxiety, is a disorder characterized by overwhelming anxiety and excessive self-consciousness in everyday social situations. People with social phobia have a persistent, intense and chronic fear of being watched and judged by others and of being embarrassed or humiliated by their own actions. Their fear may be so severe that it interferes with work or school and other ordinary activities. While many people with social phobia recognize that their fear of being around people may be excessive or unreasonable, they are unable to overcome it. They often worry for days or weeks in advance of a dreaded situation.

Social phobia can be limited to only one type of situation - such as a fear of speaking in formal or informal situations, or eating or drinking in front of others - or, in its most severe form, may be so broad that a person experiences symptoms almost any time they are around other people. Social phobia can be very debilitating - it may even keep people from going to work or school on some days. Many people with this illness have a hard time making and keeping friends.

Physical symptoms often accompany the intense anxiety of social phobia and include blushing, profuse sweating, trembling and other symptoms of anxiety such as difficulty talking, and nausea or other stomach discomfort. These visible symptoms heighten the fear of disapproval and the symptoms themselves can become an additional focus of fear. Fear of symptoms can create a vicious cycle: as people with social phobia worry about experiencing the symptoms, the greater their chances of developing the symptoms. Social phobia often runs in families and may be accompanied by depression or alcohol dependence.

Prevalence of Social Phobia
About 3.7 percent of the U.S. population ages 18 to 54 - approximately 5.3 million Americans - has social phobia in any given year. Social phobia occurs twice as often in women as in men, although a higher proportion of men seek help for this disorder. The disorder typically begins in childhood or early adolescence and rarely develops after age 25.

Symptoms
A diagnosis of social phobia is made only if the avoidance, fear or anxious anticipation of encountering the social or performance situation interferes with the person's daily routine, occupational functioning or social life, or if the person is markedly distressed by having the phobia.

Symptoms include:

Fear of one or more social or performance situations if the person is exposed to unfamiliar people and the individual fears that he or she will behave in a manner that causes embarrassment

Exposure to social situation causes intense anxiety

The level of anxiety is recognized by the individual as excessive

The feared situation must be avoided or endured with anxiety and distress

The avoidance, anxious anticipation or distress interferes significantly with the person's social, academic or occupational functioning

Causes
Research to define causes of social phobia is ongoing. Some investigations implicate a small structure in the brain called the amygdala in the symptoms of social phobia. The amygdala is believed to be a central site in the brain that controls fear responses.

Animal studies are adding to the evidence that suggests social phobia can be inherited. In fact, researchers supported by the National Institute of Mental Health (NIMH) recently identified the site of a gene in mice that affects learned fearfulness.

One line of research is investigating a biochemical basis for the disorder. Scientists are exploring the idea that heightened sensitivity to disapproval may be physiologically or hormonally based.

Other researchers are investigating the environment's influence on the development of social phobia. People with social phobia may acquire their fear from observing the behavior and consequences of others, a process called observational learning or social modeling.

Obsessive-Compulsive Disorder
Obsessive-ompulsive disorder (OCD), one of the anxiety disorders, is a potentially disabling condition that can persist throughout a person's life. The individual who suffers from OCD becomes trapped in a pattern of repetitive thoughts and behaviors that are senseless and distressing but extremely difficult to overcome. OCD occurs in a spectrum from mild to severe, but if severe and left untreated, it can destroy a person's capacity to function at work, at school or even in the home.

For many years, mental health professionals thought of OCD as a rare disease because only a small minority of their patients had the condition. The disorder often went unrecognized because many of those afflicted with OCD, in efforts to keep their repetitive thoughts and behaviors secret, failed to seek treatment. This led to underestimates of the number of people with the illness. However, a survey conducted in the early 1980s by the National Institute of Mental Health (NIMH) - the Federal agency that supports research nationwide on the brain, mental illnesses and mental health - provided new knowledge about the prevalence of OCD. The NIMH survey showed that OCD affects more than 2 percent of the population, meaning that OCD is more common than such severe mental illnesses as schizophrenia, bipolar disorder or panic disorder. OCD strikes people of all ethnic groups. Males and females are equally affected. The social and economic costs of OCD were estimated to be $8.4 billion in 1990.

Although OCD symptoms typically begin during the teenage years or early adulthood, recent research shows that some children develop the illness at earlier ages, even during the preschool years. Studies indicate that at least one-third of cases of OCD in adults began in childhood. Suffering from OCD during early stages of a child's development can cause severe problems for the child. It is important that the child receive evaluation and treatment by a knowledgeable clinician to prevent the child from missing important opportunities because of this disorder.

Symptoms

Obsessions
These are unwanted ideas or impulses that repeatedly well up in the mind of the person with OCD. Persistent fears that harm may come to self or a loved one, an unreasonable concern with becoming contaminated, or an excessive need to do things correctly or perfectly are common. Again and again, the individual experiences a disturbing thought, such as, "My hands may be contaminated, I must wash them," "I may have left the gas on" or "I am going to injure my child." These thoughts are intrusive, unpleasant and produce a high degree of anxiety. Sometimes the obsessions are of a violent or a sexual nature, or concern illness.

Compulsions
In response to their obsessions, most people with OCD resort to repetitive behaviors called compulsions. The most common of these are washing and checking. Other compulsive behaviors include counting (often while performing another compulsive action such as hand-washing), repeating, hoarding, and endlessly rearranging objects in an effort to keep them in precise alignment with each other. Mental problems, such as mentally repeating phrases, list-making or checking are also common. These behaviors generally are intended to ward off harm to the person with OCD or others. Some people with OCD have regimented rituals while others have rituals that change. Performing rituals may give the person with OCD some relief from anxiety, but it is only temporary.

People with OCD show a range of insight into the senselessness of their obsessions. Often, especially when they are not actually having an obsession, they can recognize that their obsessions and compulsions are unrealistic. At other times they may be unsure about their fears or even believe strongly in their validity.

Most people with OCD struggle to banish their unwanted, obsessive thoughts and to prevent themselves from engaging in compulsive behaviors. Many are able to keep their obsessive-compulsive symptoms under control during the hours when they are at work or attending school. But over the months or years, resistance may weaken, and when this happens, OCD may become so severe that time-consuming rituals take over the sufferers' lives, making it impossible for them to continue activities outside the home.

OCD sufferers often attempt to hide their disorder rather than seek help. Often they are successful in concealing their obsessive-compulsive symptoms from friends and coworkers. An unfortunate consequence of this secrecy is that people with OCD usually do not receive professional help until years after the onset of their disease. By that time, they may have learned to work their lives - and family members' lives - around the rituals.

OCD tends to last for years, even decades. The symptoms may become less severe from time to time, and there may be long intervals when the symptoms are mild, but for most individuals with OCD, the symptoms are chronic.

Causes
The old belief that OCD was the result of life experiences has been weakened before the growing evidence that biological factors are a primary contributor to the disorder. The fact that OCD patients respond well to specific medications that affect the neurotransmitter serotonin suggests the disorder has a neurobiological basis. For that reason, OCD is no longer attributed only to attitudes a patient learned in childhood - for example, an inordinate emphasis on cleanliness, or a belief that certain thoughts are dangerous or unacceptable. Instead, the search for causes now focuses on the interaction of neurobiological factors and environmental influences, as well as cognitive processes.

OCD is sometimes accompanied by depression, eating disorders, substance abuse disorder, personality disorders, attention deficit disorder, or another of the anxiety disorders. Coexisting disorders can make OCD more difficult both to diagnose and to treat.

In an effort to identify specific biological factors that may be important in the onset or persistence of OCD, NIMH-supported investigators have used a device called the positron emission tomography (PET) scanner to study the brains of patients with OCD. Several groups of investigators have obtained findings from PET scans suggesting that OCD patients have patterns of brain activity that differ from those of people without mental illness or with some other mental illness. Brain-imaging studies of OCD showing abnormal neurochemical activity in regions known to play a role in certain neurological disorders suggest that these areas may be crucial in the origins of OCD. There is also evidence that treatment with medications or behavior therapy may induce changes in the brain that coincide with clinical improvement.

Preliminary studies of the brain using magnetic resonance imaging showed that the subjects with obsessive-compulsive disorder had significantly less white matter than did normal control subjects, suggesting a widely distributed brain abnormality in OCD. Understanding the significance of this finding will be further explored by functional neuroimaging and neuropsychological studies.

Symptoms of OCD are seen in association with some other neurological disorders. There is an increased rate of OCD in people with Tourette's syndrome, an illness characterized by involuntary movements and vocalizations. Investigators are currently studying the hypothesis that a genetic relationship exists between OCD and the tic disorders.

Other illnesses that may be linked to OCD are trichotillomania (the repeated urge to pull out scalp hair, eyelashes, eyebrows or other body hair), body dysmorphic disorder (excessive preoccupation with imaginary or exaggerated defects in appearance), and hypochondriasis (the fear of having - despite medical evaluation and reassurance - a serious disease). Genetic studies of OCD and other related conditions may enable scientists to pinpoint the molecular basis of these disorders.

Other theories about the causes of OCD focus on the interaction between behavior and the environment and on beliefs and attitudes, as well as how information is processed. These behavioral and cognitive theories are not incompatible with biological explanations.

A person with OCD has obsessive and compulsive behaviors that are extreme enough to interfere with everyday life. People with OCD should not be confused with a much larger group of individuals who are sometimes called "compulsive" they hold themselves to a high standard of performance and are perfectionists and very organized in their work and even in recreational activities. This type of "compulsiveness" often serves a valuable purpose, contributing to a person's self-esteem and success on the job. In that respect, it differs from the life-wrecking obsessions and rituals of the person with OCD.